<!DOCTYPE>
<html>

<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<!--[if lt IE 9]><script language="javascript" type="text/javascript" src="/jqplot/excanvas.min.js"></script><![endif]-->
<script type="text/javascript">
	var list=[];
	var currentC;
	var _e={};
    var cricle = function(x,y,r){
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    	this.y=y;
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			ctx.arc(this.x,this.y,this.r,2*Math.PI,0,true);
			if ((x && y && ctx.isPointInPath(x, y) && !currentC )||this.isCurrent) {

					
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			for(var i=0;i<10;i++){
				var c=new cricle(20*i,20*i,5*i);
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				list.push(c);
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		var x = e.clientX - canvas.offsetLeft;
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		canvas.width = canvas.width;
		if (canvas.getContext){
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			for(var i=0;i<list.length;i++){
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		var canvas = document.getElementById('tutorial');
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		var x = e.clientX - canvas.offsetLeft;
		var y = e.clientY - canvas.offsetTop;

		if(currentC){
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			currentC.y=parseInt(y+(y-currentC.y)/5);
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		_e=e;

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			var x = e.clientX - canvas.offsetLeft;
			var y = e.clientY - canvas.offsetTop;
			if(currentC)
				currentC.isCurrent=false;
			currentC=null;
			reDraw(e);
			_e=e;
			var showTimer=setInterval(function(e){
				reDraw(e);
			},10,_e);
			canvas.onmousemove=show;

			document.onmouseup=function(){
				if(currentC)
					currentC.isCurrent=false;
				currentC=null;
				canvas.onmousemove=null;
				clearInterval(showTimer);
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		}
	}
</script>
<style type="text/css">
  canvas { border: 1px solid black; }
</style>
</head>
<body style="background:#eeeeee;">
    <canvas id="tutorial" width="1000" height="550" style="z-index:100;display:block;position:absolute;"></canvas>
</body>
</html>